RE: Location of the tnsnames.ora file in 10.2.0.1 instant client

Not sure if it's the same for instant client, but I think you can set TNS_ADMIN to point it to the right directory, or check the oracle.key file in your ORACLE_HOME/bin directory and that should direct you to the right area of the registry. There are metalink notes with more details - just search for "oracle.key".

Regards,
Brandon

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